A major focus of my previous research has been the temporal representation of communication sounds. Specifically, I have investigated the applicability of networks of nonlinear oscillators to the processing of naturally produced rhythms. Crawford has been working with an animal (Pollimyrus: Mormyridae) whose processing of acoustic signals is accomplished mainly via temporal mechanisms. Thus, Pollimyrus provides the ideal animal model in which to study temporal representation in the vertebrate auditory system. The goal of the proposed research is to develop dynamic models of temporal processing of in the auditory system, and test these against alternative models in new physiological experiments. I will spend the first six months analyzing known temporal mechanisms, evaluating these with respect the existing data on Pollimyrus, and formulating new dynamic models based on existing data. Over the following six months, I plan to design new physiological experiments and test the new models. I will also spend time during the first year evaluating the fits, and redesigning the models as necessary. Activities during the second year will follow from the results of the first year, especially the results of the early experiments with respect to the dynamic models. I plan to spend year two developing a model of temporal processing that follows the coding of communications sounds from stimulus through representation in the midbrain of Pollimyrus.